{"nrhp_refnum":"87001530","name":"Butler Flats Light Station","other_names":[],"category":"structure","location":{"address":"New Bedford Channel","address_restricted":false,"city":"New Bedford","county":"Bristol County","state":"MA","lat":41.60196291200003,"lon":-70.89782129399998,"geom_source":"nps_gis"},"listed_date":"1987-06-15","is_nhl":false,"nhl_designated_date":null,"areas_of_significance":["Engineering","Transportation","Architecture","Maritime History"],"significance_levels":["national","state","local"],"summary":{"what_it_is":"A 53-foot caisson-type lighthouse built in 1898 on a marine site in New Bedford Channel at the entrance to New Bedford Harbor, Massachusetts. It has a cast iron caisson foundation and a three-story brick tower.","why_significant":"The nomination argues the light retains integrity of location, design, setting, materials and workmanship and is associated with the development of aids to navigation in Massachusetts. It is a well-maintained example of caisson construction and the only one of its type designed by a known marine architect. The brick tower with building-style detailing is described as unusual and perhaps unique among caisson harbor lights.","narrative":"Butler Flats Light Station is a 53-foot white and black cylindrical lighthouse standing in New Bedford Channel at the entrance to New Bedford Harbor. Completed on April 30, 1898, it rests on a cast iron caisson foundation set on the soft mud bottom, with curved plates at the top to deflect waves. Its three-story tower is built of brick with details such as brick window sills and arches, which is unusual among caisson harbor lights. The watchstanders room and lantern house are cast iron. F. Hopkinton Smith designed and built the station. Two officers and five enlisted men once lived there to tend the light and fog signal. The Coast Guard automated the station in 1978 after a nearby hurricane barrier made it less necessary, and a local campaign helped save it. It is valued as a well-maintained caisson light and the only one of its type by a known marine architect. Access is by boat only.","period_of_significance":null,"architect_builder":"F. Hopkinton Smith","architectural_style":"Caisson tank light (caisson harbor light type)","criteria":["A","B","C"],"status_note":"Active and unmanned; automated in 1978, with maintenance by a private organization under a Coast Guard license.","vacant_flag":null,"machine_generated":true,"model":"claude-sonnet-5-5","prompt_version":"v1.0-2026-10-29","generated_at":"2026-10-29 02:13:02.275923-05","source_pdf":"https://s3.amazonaws.com/NARAprodstorage/opastorage/live/89/7896/63789689/content/electronic-records/rg-079/NPS_MA/87001530.pdf"},"photo":{"url_800":"https://nationalhistoricalregister.com/media/87001530/eb9685e825-800.webp","url_1600":"https://nationalhistoricalregister.com/media/87001530/eb9685e825-1600.webp","licence":"CC BY 2.0","author":"Lara; cropped and color-corrected by Daniel Case 2008-07-14","credit_html":"<a href=\"https://commons.wikimedia.org/wiki/File:Butler_Flats_Light,_New_Bedford,_MA.jpg\" rel=\"noopener\">Lara; cropped and color-corrected by Daniel Case 2008-07-14</a>, <a href=\"https://creativecommons.org/licenses/by/2.0\" rel=\"license noopener\">CC BY 2.0</a>, via Wikimedia Commons","source_page":"https://commons.wikimedia.org/wiki/File:Butler_Flats_Light,_New_Bedford,_MA.jpg"},"district":null,"sources":{"nps_snapshot_date":"2026-05-22","nara_catalog":"https://catalog.archives.gov/id/63789689","wikipedia":"https://en.wikipedia.org/wiki/Butler_Flats_Light","wikidata":"https://www.wikidata.org/wiki/Q5002608"},"indexable":true,"url":"https://nationalhistoricalregister.com/massachusetts/bristol-county/butler-flats-light-station-87001530/"}